'82 GS850 No Revs

[EDubs]

Hi everyone, relatively new member and my first posting. My problem now is that the bike will not rev up from an idle, either with the airbox on or off, but I did find something that will make it run good, but its not a fix I want to do for fear of hurting my bike.

Starting off I've cleaned the carbs and replaced needles and seats (old ones were well worn to put it nicely), o-rings between the fuel transfer pipes (Solved my fuel leaks out of the carbs). I haven't yet replaced the intake boots, thats in the future for the bike (they're pretty hard and I can see some very small cracking near the mounting holes), unless that could be the problem then it will be sooner. I did however replace the rotting o-ring from behind the intake boot.

As for my fix, I found that placing my fingers over what John Bloemer calls in his carb clean and repair pictorial, an air passage hole, "http://www.thegsresources.com/images/carbs/084_Spray%20air%20passage%20across%20from%20air%20 jet.jpg" that the bike will run like a raped ape. Without these holes covered the bike just dies as soon as any throttle is applied to it. The bike will as will get some revs from the choke, but only as much as the choke can give, anytime the throttle is applied it dies.

I am wondering as to why plugging these air passage holes will make the bike suddenly run so well, while when they are left to their own devices it will not take any throttle. Any advice and or guidance would be greatly appreciated, as I would really like to get this bike running and back out on the road.

[1978GS1000custom]

how did you clean the carb bodies? did you dip them or sonic them? it sounds like to have a blockage somewhere in the carbs or perhaps a petcock thats not supplying enough gas. there are alot of very small passages inside the carb bodies and they clog easily requiring proper carb body cleaning before a rebuild. if you send me just the stripped bodies i can sonic clean them for 30.00 including shipping if that helps.cliff

[rustybronco]

My problem now is that the bike will not rev up from an idle, either with the airbox on or off, but I did find something that will make it run good, but its not a fix I want to do for fear of hurting my bike.

It won't run properly without an air box in place.

did you re-seal the air box side covers and do you have a properly oiled air filter installed?

[Steve]

First of all,

BassCliff will be along shortly with his little welcome.

What holes are you calling the "air passage holes"? In the carb intake, there are two holes. One is at about the 8 o'clock position, that is your pilot air jet. You can remove that for cleaning, but put it back in for proper operation. There is another hole at about the 4 o'clock position, nothing comes out of there, but it should be open. Try spraying carb cleaner and compressed air through it to be sure.

If you are blocking the pilot air jet hole, that means that your pilot fuel jet might be plugged. You are referring to a good pictorial, just hope you followed all the instructions in it. Did you just spray the parts clean or did you dip the carbs? If you dipped, how long? Unless you know that the bike has worked recently, you will be better off with a full day-long dip for each carb body. Follow that with mechanical poking through all the jet holes (I use a strand of copper wire as it is softer than the brass and won't scratch it), then spray with carb cleaner and compressed air.

If the carbs have been cleaned properly and preliminary adjustments are close enough for the bike to run, you can do a quick test with a shop rag. Fold the rag in half, drape it over the carb intakes and clamp it to the outer two carb throats. You can use a hose clamp or a zip-tie, but the rag should be reasonably taut over the intakes. Now you should have enough throttel response to actually go for a ride around the block, but the restriction is not appropriate for doing jetting checks. For that, you will have to use the filters that you plan on running with.

.

[BassCliff]

Greetings and Salutations!!

Hi Mr. EDubs,

Please don't take any shortcuts with your carbs. Do them once, the correct way, and you'll never have to worry about them again. If you at all suspect the intake boots and o-rings, just replace them and save yourself a lot of future grief. Seal the airbox. These 850s love tight, leak-free intake systems. OK, now I'll do my "welcome thing".

Here is your own all-encompassing, ever enlightening, magical, mystical, mythical, mind-expanding, spiritually uplifting "mega-welcome". Please take notice of the "Top 10 Common Issues", the Carb Rebuild Series, and the Stator Papers. Now let me roll out the welcome mat for you...

Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff